This invention relates to wabbler plate engine mechanisms and has as its aim to introduce a variable displacement facility thereto which is simple in operation and preserves the stability of the mechanism. Such mechanisms are useful in internal and external combustion engines and in pumps.
Wabbler plate engine mechanisms broadly comprise a plurality of piston/cylinders arranged around a crankshaft axis, and coupled to arms of a wabbler plate rotatably mounted on a wabbler carrier, which is obliquely mounted on a crankshaft. As the crankshaft rotates, each piston is forced to reciprocate in its cylinder, and vice versa. These mechanisms are known for example from U.S. Pat. No. 2, 258, 127 to Almen. The mechanism described in that patent resolved a number of problems inherent in wabbler plate mechanisms, particularly that of stabilizing the mechanism while permitting the wabbler plate arms to oscillate relative to each piston in a plane perpendicular to the axis thereof. Almen describes the provision of ball races on curved surfaces of the wabbler plate and crankcase which confine a ball at the intersection thereof. As these races are only in alignment at the top dead centre and bottom dead centre positions of the pistons, the ball can never become displaced. The Almen mechanism is quite satisfactory for fixed displacement but is not adapted to variable displacement.